<template> 
 <div>
 <p>coo:{{coo}}</p>
 <button @click="startUpRocket">我要发射火箭</button>
 </div>
</template>
<script>
 export default {
 name:'childDomChild',
 props:['coo'],
 methods:{
 startUpRocket(){
 this.$emit("upRocket");
 console.log("startUpRocket")
 }
 }
 }
</script>